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101.
The ganglioside composition of the cerebral hemispheres of young and adult rats of either sex has been herein assessed for the first time. In females, the total ganglioside content at any age, the content of GM1, GD1a, and GD1b at 8 days, and the content of GM1, GD1b, GT1b, and GQ1b at 60 days were higher in the right than in the left hemisphere. In males, no difference was observed. Concerning the ceramide moiety, a difference was displayed by C18:1 long-chain base in GD1a, whose proportion was higher in the left than in the right hemisphere of females aged 8 days. The comparison between homolateral hemispheres of rats of different sex revealed several differences. On average, in 8-day-old animals, the content of gangliosides was higher in females than in males. At 60 days the amount of gangliosides was on average lower in females than in males, even if with some exception. The data obtained with the current investigation show the existence of a ganglioside lateralization in rat brain, exclusively in females, and almost entirely at charge of the oligosaccharide portion. Moreover, age-dependent changes of ganglioside pattern and content show a dependence on brain lateralization. J. Neurosci. Res. 50:643–648, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
102.
T1‐weighted fluid‐attenuated inversion recovery (FLAIR) sequence is a relatively new pulse sequence for intracranial MR imaging. This study was performed to compare the image quality of T1‐weighted FLAIR with the T1‐weighted FSE sequence. Twenty patients with brain lesions underwent T1‐weighted fast spin‐echo (FSE) and T1‐weighted FLAIR during the same imaging session. Four quantitative and three qualitative criteria were used to compare the two sequences after contrast. Two of four quantitative criteria pertained to lesion characteristics: lesion to white matter (WM) contrast‐to‐noise ratio (CNR) and lesion to cerebrospinal fluid (CSF) CNR, and two related to signals from normal tissue: grey matter to WM CNR and WM to CSF CNR. The three qualitative criteria were conspicuousness of the lesion, the presence of image artefacts and the overall image contrast. Both T1‐weighted FSE and FLAIR images were effective in demonstrating lesions. Image contrast was superior in T1‐weighted FLAIR images with significantly improved grey matter‐WM CNRs and CSF‐WM CNRs. The overall image contrast was judged to be superior on T1‐weighted FLAIR images compared with T1‐weighted FSE images by all neuroradiologists. Two of three reviewers considered that the FLAIR images had slightly increased imaging artefacts that, however, did not interfere with image interpretation. T1‐weighted FLAIR imaging provides improved lesion‐to‐background and grey to WM contrast‐to‐noise ratios. Superior conspicuity of lesions and overall image contrast is obtained in comparable acquisition times. These indicate an important role for T1‐weighted FLAIR in intracranial imaging and highlight its advantage over the more widely practiced T1‐weighted FSE sequence.  相似文献   
103.
Prefabricated, patient-specific alloplastic implants for cranioplasty reduce surgical complexity, decrease operative times, minimize exposure and risk of contamination, and have resulted in improved aesthetic results. However, in creating a prefabricated custom implant using a patient’s computed tomography data, a stable, unalterable defect must be clearly defined before surgery. In the event that an intraoperative modification of an exiting skull defect is required, or in cases of tumour resection in which the size of the skull defect is unknown preoperatively, these prefabricated implants cannot be used. The ideal method for alloplastic cranioplasty would enable cost-effective creation of a patient-specific implant with the capacity for intraoperative modification.The present article describes a novel technique of cranioplasty that uses a patient’s computed tomography data to create a custom forming tool (ie, mold), enabling intraoperative creation of a patient-specific titanium mesh implant. The utility of these implants in creating a custom reconstructive solution in cases in which the size of the skull defect is unknown preoperatively will be demonstrated using two case presentations.  相似文献   
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About 10–15% of patients with acquired aplastic anemia (AAA) have resistant/recurrent disease not eligible for standard treatment like hematopoietic stem cell transplantation and/or combined immunosuppression. We report a 17‐year‐old male with an 11 years history of AAA who, after two courses of immunosuppression, was red cell transfusion‐dependent, severely thrombocytopenic, refractory to platelet transfusion, had iron overload and post‐transfusion HCV infection. This patient achieved transfusion independence from platelets and normalized Hb after treatment with the anti‐TNF agent Etanercept. Over a 12 months follow‐up he experienced only transient increase of liver transaminases. Pediatr Blood Cancer 2009;52:522–525. © 2008 Wiley‐Liss, Inc.  相似文献   
110.
Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare recessive disorder resulting from mutations in the autoimmune regulator ( AIRE ) gene. There is no information on AIRE mutations in Indians. In a cross-sectional study, nine patients (eight families), from four referral hospitals in India, were studied for AIRE mutations by direct sequencing. We screened for new mutations in 150 controls by allele-specific PCR. The patients had 1–7 known components of APECED. Three patients had unusual manifestations: presentation with type 1 diabetes; chronic sinusitis and otitis media; and facial dysmorphism. All patients carried homozygous, probably recessive, AIRE mutations. Two unrelated patients from a small in-bred community (Vanika Vaisya) in south India carried an unreported missense mutation, p.V80G, in the N-terminal caspase recruitment domain. Another unique mutation, p.C302X, resulting in a truncated protein with deletion of both zinc-finger domains, was detected in a patient from Gujarat. Neither mutation was detected in controls. Other mutations, previously described in Caucasians, were: 13 base pair deletion (p.C322fsX372) in 4 (38%), and Finn-major (p.R257X) and p.R139X (Sardinian) mutation in one subject each. In conclusion, in this first series of APECED in Indians, we detected AIRE mutations previously reported in Caucasians, as well as unique mutations. Of these, p.V80G is possibly an ancestral mutation in an in-bred community.  相似文献   
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